<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
</head>
<body>

</body>
<script>
  console.log(typeof 1)               // number
  console.log(typeof '')               // string
  console.log(typeof null)               //  object
  console.log(typeof undefined)               //  undefined
  console.log(typeof Symbol(0))               //  symbol
  console.log(typeof [])               //   object
  console.log(typeof {})               //  object
  console.log(typeof (() => {}))               //  function
</script>
</html>